A new growth model of the northeastern Tibetan Plateau from high-resolution seismic imaging by improved double-difference tomography

Sun，Quan1,2; Pei，Shunping1,2,3; Cui，Zhongxiong4; Chen，Y. John5; Liu，Yanbing1,2; Xue，Xiaotian1,2; Li，Jiawei1,2; Li，Lei1,2; Zuo，Hong1,2

2021-01-05

10.1016/j.tecto.2020.228699

TECTONOPHYSICS   影响因子和分区

0040-1951

1879-3266

High-resolution 3-D P and S wave velocity (Vp and Vs) models of the crust and uppermost mantle beneath the northeastern (NE) Tibetan Plateau and the surrounding areas were obtained by applying an improved double-difference seismic tomography method on abundant body wave travel-time data of local and regional earthquakes collected from 1985 to 2018. The improved method not only increases constraints from observed Moho depth information but also incorporates the later-arriving Pg and Sg phases to improve the ray coverage in the middle-lower crust and uppermost mantle. The results show significant low-velocity anomalies in the crust beneath the NE Tibetan Plateau and high-velocity features beneath the surrounding stable Alxa and Ordos blocks. The areas near the boundaries of the cratonic blocks show high velocity in the upper crust and uppermost mantle beneath the Hexi Corridor, and high velocity in the upper crust beneath the Liupan Shan belt. Both of those regions have significant low-velocity anomalies in the middle-lower crust similar to the Tibetan Plateau, which suggests they probably were parts of the Alxa and Ordos blocks respectively, and were cut off from the two cratonic blocks during the lateral expansion of the Tibetan Plateau because of middle-lower crustal ductile deformation and asthenospheric flow. We propose a new tectonic model controlled by middle-lower crustal ductile deformation and asthenospheric flow to illuminate the tectonic evolution and growth mechanism of the NE Tibetan Plateau.

Alxa block Double-difference tomography Geodynamic model NE Tibetan Plateau Ordos block Seismic velocity structure

EI ; SCI

英语

其他

National Key R&D Program of China[2017YFC1500303] ; Strategic Priority Research Program of Chinese Academy of Sciences[XDA20070302] ; National Natural Science Foundation of China[41674090,41490610]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:000608867300005

ELSEVIER

20205109658400

Deformation ; Geodynamics ; Shear waves ; Wave propagation ; Velocity ; Tectonics

Geology:481.1 ; Geophysics:481.3 ; Seismology:484 ; Mechanics:931.1

GEOSCIENCES

2-s2.0-85097783303

Scopus

1.Key Laboratory of Continental Collision and Plateau Uplift,Institute of Tibetan Plateau Research,Chinese Academy of Sciences (CAS),Beijing,100101,China
2.University of Chinese Academy of Sciences,Beijing,100049,China
3.CAS Center for Excellence in Tibetan Plateau Earth Sciences,Chinese Academy of Sciences (CAS),Beijing,100101,China
4.Department of Earth and Environmental Sciences,Lehigh University,Bethlehem,18015,United States
5.Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China

Sun，Quan,Pei，Shunping,Cui，Zhongxiong,et al. A new growth model of the northeastern Tibetan Plateau from high-resolution seismic imaging by improved double-difference tomography[J]. TECTONOPHYSICS,2021,798.

Sun，Quan.,Pei，Shunping.,Cui，Zhongxiong.,Chen，Y. John.,Liu，Yanbing.,...&Zuo，Hong.(2021).A new growth model of the northeastern Tibetan Plateau from high-resolution seismic imaging by improved double-difference tomography.TECTONOPHYSICS,798.

Sun，Quan,et al."A new growth model of the northeastern Tibetan Plateau from high-resolution seismic imaging by improved double-difference tomography".TECTONOPHYSICS 798(2021).